According to Peter Beinart's The Icarus Syndrome, CIA analysts during the late 1950s considered putting radioactive dust in Fidel Castro's shoes.

Why? They didn't want to kill him, but instead they wanted his hair to fall out. It seems that the folks at Langley believed that Latin leaders kept their power by demonstrating their virility. They actually thought that Cubans would've staged a coup d'etat if a leader went bald. Ike passed on that one... maybe because he had a shiny dome? DBM